Spirit level

ABSTRACT

The present invention comprises a spirit level in which the vial thereof has a cylindrical outer surface and a curved inner surface. The curved inner surface is formed during the molding of the vial by taking advantage of the memory and natural resiliency of the plastic used.

United States Patent 1,225,132 5/1917 Johnson 2,576,202

Inventor Sydney Jacofl Mlueoh, N.Y.

Sept. 26, 1968 July 20, 1971 Great Neck Saw Manufacturers, lnc. Mineola, N.Y.

Appl. No. Filed Patented Assignee SPIRIT LEVEL 9 (Ilnims, 10 Drawing Figs.

U.S.Cl 33/211 lnt.Cl G016 9/24 Field of Search 33/21 1, 207

References Cited UNITED STATES PATENTS 11/1951 Wu11sch1eger 33/211 2,646,628 7/1953 Shaler 33/211 2,810,206 10/1951 Ziemann 33/211 2,948,066 9/1960 Rosenholm 33/207 2,993,281 7/1961 Dock 33/211 3,311,990 4/1967 Wright 33/211 3,456,354 7/1969 Wright 33/211 876,720 1/1908 King 33/211 2,502,235 3/1950 Schultes 33/213 Primary Examiner-Leonard Forman Assistant ExaminerDennis A. Dearing Attorney-Norman N. Holland ABSTRACT: The present invention comprises a spirit level in which the vial thereof has a cylindrical outer surface and a curved inner surface. The curved inner surface is formed during the molding of the vial by taking advantage of the memory and natural resiliency of the plastic used.

; ticularly' to an improved spirit level for .present'spirit levels isincreased substantially.

.- wherein; I v

FIGLI is aperspective view show 1 accordance with the present invention;

. of the present invention; 7 I I I BIG-. 17 is a perspective view. showing ofthe-presentinvention;

I t t of the level vial;-'a'nd tion-of the levelvial. I I I I I I r I let'erIing more particularly to the drawings the spirit level 1 comprises a body 2 in the shape of an I-bea'm having parallel opposed bearing surfaces 3 connectedjby a web'4.The web4 j mounted a level vial .10. The web .4 base I surrounding opening5 which permits the beiatta'chedthereto'.

I lhe present invention relates to a spirit level and morepar.

the-levelof surfaces and thelike.

1 Heretofore a number-of spirit levels have been designed for "thisvpurpose. Somel'of these levels require curved level vials.

. Other levelsin' use are provided with level vials which'have a cylindrical 'eittcrior and an internalcurved cavity which permits the. aiibiibble-thereivithinto remain uppermost. However,- such level vials have. heretofore been molded and the curved interior of each vial is formed separately by machining the interior. This -isa costly operation so that the cost of The, present invention avoids these drawbacks and provides 'Another'object of the, presentinvention' is the provision of an improved level :vial which canbe automatically. mounted in the proper position both axially and'radially without special 'tools.

- Anotherobject of the present invention is the provision of t i an improvedmethod ofmakingthelevelvial. v

" Othe r and furtherobjects of; theinvention will beobvious up'onanQunderstanding of the illustrative embodiment about d,;"o'rjwill be indicated in the appended claims,

'and variousf=advantages.not referredto herein-will occur to one skilled in practice.

the-art upon employment'of the invention in accuratelydetermining its other end 17 openand adapted to be plugged by a suitable the vial, are provided to act as level indicators.

19 equidistant from the plug 18. Spaced raised ridges I ends of The internal configuration of the vial comprises a pair of substantially straightcylindrical endportions 22 between which is interposed a curved central portion 20 which'afcts' to accommodate the'air bubble; 21 ther'ewithin. The'air bubble 211: formed by inserting fluid 2 mm the vial havinga volume less than the internal volume of the vialJPreferably the vial is made of anamber color to facilitate seeing the air bubble;

in assembling the vial, the fluid 23is first inserted therein and the vial is plugged. by the plug 18. The vial is then mounted on the'cover 6 by inserting the key 13 into slot 12in curved surface 11. The covers are then mounted on the web 4 over the opening 5. t I t FIG. 6 shows an alternate construction whereby the vial 10 has a pair of flanges '30 extendingtherefrom. Each flange is provided with a pin 31 adapted to be inserted into openings 32 inthe web 4.

in FIG. 7 anotherconstruction is shown whereby the .vial 10 is provided 'withslots 35 which'are inserted into the web 4.

I an improved level vial'in which the air bubble can be easily I Another object of the present invention is the'p'rovision-of I The preferred method of forming the vial of the present invention is shown "in FIGS. 8 to 10. The vial 10 is molded in a mold 40 bya plunger 41 which has a bulged portion42 interposed between straight end portions 43. At the same time that the vial'is molded, the inner and I6 of the vial is closed. Thus the'barrel-shaped cavity 20,'-the straight portions 22 'and the closed end l6'are all formed simultaneously.

The vial and the plunger are removed from mold 40 and thereafter the plunger 41 is removed. The plastic material that forms the vial has a certain resiliency and memory. W hen the pIun'ger4I is removed from "within the ,vial cavity, the straight wall 22a-portion will be distorted by' passage of bulge 42 Apreferred embodiment of the invention has been chosen I for purposes of illustration and description and is shown in the accompanying,drawings, forming a part of the specification in'ga spirit levelmade in Fl G.2 is a fragmentary plan viewthereof; 1

' 'FIG. 3 .is .an'explodedview showing the'position of the various components of the level;

FIG. 6. isa perspective viewshowing another. embodiment FIG. 8 is a sectional view'showing the first'step in the I preferred method of forming'thelevel vial;

FIG. 9 is a perspective view 'showinganother step inthe for f FIG. 10 is .asimilar view showing the last step in the formais provided with at least one'opening therein. On each side of the'iopening 15 "a vial cover 6 .-is provided between which is cover portions' 6 to Each cover portion -6 comprisesa transparent border area 8 anotherembodiment I plurality of holes7 thereth'rough. However, the natural resiliency and memory-of .the plastic material will cause wallZZa to resume its original straight shape. The center portion will remain curved and will form the barrel-shaped interior cavity 20 that will accommodate the air bubbleyH'ence, in a single operation the vial is formed having a cavity with substantially straight end portions 22-22a and a curved inner portion 20. This eliminates the necessity of machining thevial as has heretofore been necessary. I I I lt wi ll thus be seen that the present invention provides an improved easy-to-read level which'is easier to use and whichcan be easily mounted intoplace without special machinery and without-special skill. The present invention also provides an .improved'method of making a level vial/As many widely difl'erent embodiments of this invention may bemade without departing from the spirit or scope of this disclosure, it is tobe understood that the invention is not to be limited to the severalspecific embodiments disclosed herein except to the extent necessitated by the appended claims.

Having thus described myinvention', I claim:

1; A spirit level comprising a reference surface and a body portion, an opening in said body portion, a single vial mounted in said opening, said vial comprising a substantially straight cylindrical outer surface and a bore, said bore having a por- 1 with a circular viewing-area 9'. Along the edge of the viewing I area -9 a.curved vialvreceivingjournalsurface 11 is formed which-is adapted to receive vial '10. At least one of the curved receiVingswfaces maybe provided with a slot "to receive a I key 13 which may-extend from the vial 5. i y i'Each level vial. l0 has an outside cylindrical surface 14 and ;ill .ln olded from a plastic .m'mrnl, which mayhem-acrylic v composition. The 'vlal li hollow and has one end l dclosed and tion thereof curved away from the internal axis of the vial, a pair of covers, each of said covers having a transparent-viewing area and an integral surrounding rim area on a plane offset from-the plane of the viewing area,said rim area having a portion adapted to be attached to said body portion whereby each of said covers is held in place, and each cover being provided with diametrically opposed concave, curved receiving areas in its rim area to receive the opposed ends of the vialso that the vial is received between said pair of covers, at least one of said diametrically opposed concave, curved receivingareas having made'of a transparent plastic material.

preventing move- 4. A spirit level as claimed in claim 1, wherein the interior of said vial has a pair of straight portions with a curved portion interposed therebetween.

5. A spirit level as claimed in claim 4, wherein said vial has a closed end integral with the outer surface thereof.

6. In a spirit level having a cover with key-receiving slots, a spirit level vial comprising a generally cylindrical plastic transparent outer body, a bore within said body, one end of said vial having a wall integral with and one piece with the body and closing one end of the bore, the other end of the bore being open, said bore having a portion thereof curved away from the internal axis of the vial, spaced keys integral with and extending outwardly from the outer body portion of the vial adjacent the ends thereof for reception in cooperating relation in the key-receiving slots to prevent rotational movement of the vial, said spaced keys being in longitudinal alignment with each other.

7. A vial as claimed in claim 6, wherein the interior of said vial has a pair of straight portions with a curved portion interposed therebetween.

8. A vial as claimed in claim 6, wherein the opposite end of the vial is closed by a plug.

9. A spirit level as claimed in claim 5, wherein the opposite end of the vial is closed by a plug. 

1. A spirit level comprising a reference surface and a body portion, an opening in said body portion, a single vial mounted in said opening, sAid vial comprising a substantially straight cylindrical outer surface and a bore, said bore having a portion thereof curved away from the internal axis of the vial, a pair of covers, each of said covers having a transparent viewing area and an integral surrounding rim area on a plane offset from the plane of the viewing area, said rim area having a portion adapted to be attached to said body portion whereby each of said covers is held in place, and each cover being provided with diametrically opposed concave, curved receiving areas in its rim area to receive the opposed ends of the vial so that the vial is received between said pair of covers, at least one of said diametrically opposed concave, curved receiving areas having a slot and said vial having a key extending therefrom, said slot being adapted to accommodate said key for preventing movement of the vial relative to the cover portion.
 2. A spirit level as claimed in claim 1, wherein a pair of raised ridges is provided on the surface of said vial.
 3. A spirit level as claimed in claim 1, wherein the vial is made of a transparent plastic material.
 4. A spirit level as claimed in claim 1, wherein the interior of said vial has a pair of straight portions with a curved portion interposed therebetween.
 5. A spirit level as claimed in claim 4, wherein said vial has a closed end integral with the outer surface thereof.
 6. In a spirit level having a cover with key-receiving slots, a spirit level vial comprising a generally cylindrical plastic transparent outer body, a bore within said body, one end of said vial having a wall integral with and one piece with the body and closing one end of the bore, the other end of the bore being open, said bore having a portion thereof curved away from the internal axis of the vial, spaced keys integral with and extending outwardly from the outer body portion of the vial adjacent the ends thereof for reception in cooperating relation in the key-receiving slots to prevent rotational movement of the vial, said spaced keys being in longitudinal alignment with each other.
 7. A vial as claimed in claim 6, wherein the interior of said vial has a pair of straight portions with a curved portion interposed therebetween.
 8. A vial as claimed in claim 6, wherein the opposite end of the vial is closed by a plug.
 9. A spirit level as claimed in claim 5, wherein the opposite end of the vial is closed by a plug. 